Vehicle service is a biggie. Preventative maintenance is the best way to go but it can still add up to as much as fuel. Gave my truck a thorough going over last month before going into storage. New bushings, tranny oil & filter change, diff oil change & seal replacement, bunch of other parts worn that one might expect on an 11 year old near 200,000 mile truck, but it drives like new now. No rattles. No clunks.
Might need new batteries when the key gets turned again next spring but other than that it is ready to do another 15,000 mile trip to Alaska.